(57) A double-lap oil-free scroll vacuum pump is disclosed, which comprises a revolving
scroll 3 with revolving laps 26 and 27 provided on both sides of a disc, stationary
scrolls provided on their surfaces 4b, 5b facing each surface 3d, 3e of said disc
with stationary laps 6, 7 in engagement with the revolving laps 26, 27, said revolving
laps 26, 27 being arranged in frictional contact with said surfaces 4b, 5b of the
stationary scrolls, and a rotationary drive shaft 11 penetrating the stationary and
revolving scrolls and eccentrically fitted in the disc of the revolving scroll 3,
wherein the rotational drive shaft 11 drives the revolving scroll 3 to cause discharge
of compressed gas from a last compression chamber. A housing 19 is mounted on the
outer sides of the stationary scrolls, and accommodates a drive source of the rotational
drive shaft 11. Discharge passages 4d and 5d are provided for discharging compressed
gas from the sides of the surfaces 3d and 3e of the revolving scroll 3. The discharge
passages 4d and 5d extend outwardly from the housing 19.
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